/* Swimming — one stylesheet, no framework, no external font. */
:root{
  --ink:#0e1b24; --ink2:#3c5566; --line:#cddbe4; --bg:#f2f7fa; --card:#ffffff;
  --deep:#0b3550; --mid:#14688c; --aqua:#3fb0c8; --warn:#b3411f; --ok:#1d7a4c;
  --shadow:0 1px 2px rgba(11,53,80,.08),0 6px 18px rgba(11,53,80,.06);
}
*{box-sizing:border-box}
html,body{margin:0;padding:0}
body{
  background:var(--bg); color:var(--ink);
  font:16px/1.62 "Iowan Old Style","Palatino Linotype",Palatino,Georgia,"Times New Roman",serif;
  -webkit-text-size-adjust:100%;
}
.wrap{max-width:1120px;margin:0 auto;padding:26px 20px 70px}
header{margin:10px 0 26px}
h1{
  font:700 clamp(34px,6vw,58px)/1.04 "Avenir Next","Segoe UI",Roboto,-apple-system,sans-serif;
  margin:0 0 12px; letter-spacing:-.022em; color:var(--deep);
}
h2{font:600 26px/1.25 "Avenir Next","Segoe UI",Roboto,-apple-system,sans-serif;
  margin:40px 0 12px; color:var(--deep); letter-spacing:-.012em;
  border-top:2px solid var(--line); padding-top:22px}
h3{font:600 18px/1.3 "Avenir Next","Segoe UI",Roboto,-apple-system,sans-serif;
  margin:22px 0 8px; color:var(--deep)}
p{margin:0 0 14px}
.lede{font-size:19px;color:var(--ink2);max-width:64ch}
.small{font-size:14px;color:var(--ink2);line-height:1.55}
span.k-ascent{font-variant-numeric:tabular-nums}
.mono{font:13px/1.5 ui-monospace,SFMono-Regular,Menlo,Consolas,monospace}
a{color:var(--mid)}
q{quotes:"\201C" "\201D"}
code{font:13px/1.4 ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
  background:#e7eff4;padding:1px 5px;border-radius:4px}

.card{background:var(--card);border:1px solid var(--line);border-radius:12px;
  padding:16px 18px;margin:0 0 16px;box-shadow:var(--shadow)}
.grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(300px,1fr));gap:16px}
.bar{display:flex;flex-wrap:wrap;gap:10px;align-items:center;margin:0 0 10px}
.bar:last-child{margin-bottom:0}
label{font:600 13px/1 "Avenir Next","Segoe UI",Roboto,sans-serif;color:var(--ink2);
  text-transform:uppercase;letter-spacing:.05em}
select,input[type=range],button{font:inherit;font-size:15px}
select{padding:7px 10px;border:1px solid var(--line);border-radius:8px;background:#fff;color:var(--ink)}
input[type=range]{width:190px;accent-color:var(--mid)}
button{padding:8px 15px;border:1px solid var(--line);border-radius:8px;background:#fff;
  color:var(--deep);cursor:pointer;font-family:"Avenir Next","Segoe UI",Roboto,sans-serif;
  font-weight:600}
button:hover{background:#e9f2f7}
button.primary{background:var(--mid);border-color:var(--mid);color:#fff}
button.primary:hover{background:var(--deep)}
.keys{display:inline-block;border:1px solid var(--line);border-bottom-width:2px;border-radius:5px;
  padding:0 6px;background:#fff;font:600 12px/1.7 "Avenir Next","Segoe UI",Roboto,sans-serif;
  color:var(--deep)}

/* --- the screens.  NOTE: nothing here may set `display` on .screen, or [hidden] stops working
   and an invisible panel goes on eating clicks.  Layout lives on the children. --- */
.screen{margin:0 0 10px}
[hidden]{display:none !important}

.viewwrap{position:relative;border:1px solid var(--line);border-radius:12px;overflow:hidden;
  background:#9fc2d2;box-shadow:var(--shadow)}
#view{display:block;width:100%;height:auto;background:#9fc2d2}
.hud{position:absolute;left:0;top:0;right:0;padding:10px;display:flex;gap:8px;flex-wrap:wrap;
  pointer-events:none}
.hudbox{background:rgba(8,32,48,.72);color:#eef7fb;border-radius:9px;padding:6px 11px;
  font:600 24px/1.12 "Avenir Next","Segoe UI",Roboto,sans-serif;min-width:86px}
.hudbox .sub{display:block;font:500 11px/1.4 "Avenir Next","Segoe UI",Roboto,sans-serif;
  opacity:.82;text-transform:uppercase;letter-spacing:.06em}
.hudbox .small{font-size:12px;font-weight:500;opacity:.85}
.meter{height:5px;background:rgba(255,255,255,.22);border-radius:3px;margin:5px 0 2px;
  overflow:hidden}
.meter i{display:block;height:100%;background:var(--aqua)}
#hudMsg{position:absolute;left:0;right:0;top:44%;text-align:center;color:#fff;
  text-shadow:0 2px 14px rgba(4,20,32,.85)}
#hudMsg .big{display:block;font:700 46px/1.1 "Avenir Next","Segoe UI",Roboto,sans-serif}
#hudMsg #msgSmall{font:500 17px/1.4 "Avenir Next","Segoe UI",Roboto,sans-serif}

canvas#labDepth,canvas#labCross{display:block;width:100%;height:auto;border:1px solid var(--line);
  border-radius:9px;background:#fff;margin:6px 0}

.prose{max-width:74ch}
.prose h2:first-child{border-top:none}
.eq{font:16px/1.6 ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;background:#e7eff4;
  border-left:3px solid var(--mid);padding:10px 14px;border-radius:0 8px 8px 0;overflow-x:auto}
.callout{background:#fff5ec;border:1px solid #f0d2b4;border-left:4px solid var(--warn);
  border-radius:0 10px 10px 0;padding:13px 16px}
ul{margin:0 0 14px;padding-left:22px}
li{margin:0 0 7px}
ul.cols{columns:2;column-gap:26px;font-size:14px;color:var(--ink2)}
ul.cols li{break-inside:avoid}

.tbl{border-collapse:collapse;width:100%;font-size:14px;margin:0 0 16px;
  display:block;overflow-x:auto;white-space:nowrap}
.tbl caption{caption-side:top;text-align:left;font-size:13px;color:var(--ink2);
  padding:0 0 8px;white-space:normal}
.tbl th,.tbl td{border:1px solid var(--line);padding:6px 10px;text-align:left}
.tbl th{background:#e7eff4;font:600 13px/1.3 "Avenir Next","Segoe UI",Roboto,sans-serif;
  color:var(--deep)}
.tbl tr.hl td{background:#fff5ec;font-weight:600}

.tally{display:grid;grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:12px;margin:0 0 18px}
.tally>div{background:var(--card);border:1px solid var(--line);border-radius:10px;padding:12px 14px;
  box-shadow:var(--shadow)}
.tally b{display:block;font:700 27px/1.1 "Avenir Next","Segoe UI",Roboto,sans-serif;color:var(--deep)}
.tally span{display:block;font-size:12px;color:var(--ink2);text-transform:uppercase;
  letter-spacing:.05em;margin-top:3px}

.rtab{width:100%;border-collapse:collapse;font-size:15px}
.rtab th,.rtab td{border-bottom:1px solid var(--line);padding:7px 9px;text-align:left}
.rtab th{font:600 12px/1.3 "Avenir Next","Segoe UI",Roboto,sans-serif;color:var(--ink2);
  text-transform:uppercase;letter-spacing:.05em}
.rtab td.t{font:600 15px/1.3 ui-monospace,SFMono-Regular,Menlo,Consolas,monospace}
.rtab tr.me td{background:#e7f4f9}
.rtab tr.dq td{color:var(--warn)}
.rtab td.tie{color:var(--warn);font-size:12px}

footer{margin:42px 0 0;border-top:2px solid var(--line);padding-top:16px}

.pad{display:grid;grid-template-columns:1fr 1fr 1.2fr 1.2fr;gap:8px;margin:10px 0 0}
.pad button{padding:16px 6px;font-size:16px;touch-action:none;user-select:none;
  -webkit-user-select:none;-webkit-touch-callout:none;min-width:0}
.pad button.on{background:var(--deep);border-color:var(--deep);color:#fff}
#view{touch-action:none}

@media (prefers-color-scheme: dark){
  :root{--ink:#e7f1f6;--ink2:#9fb7c4;--line:#22404f;--bg:#081620;--card:#0d2231;
    --deep:#9fdcf0;--mid:#4fb6d6;--aqua:#5ecde2;
    --shadow:0 1px 2px rgba(0,0,0,.4),0 6px 18px rgba(0,0,0,.3)}
  select,button{background:#0d2231;color:var(--ink)}
  button:hover{background:#123047}
  button.primary{color:#062130}
  .keys{background:#0d2231}
  code,.eq,.tbl th{background:#12293a}
  .callout{background:#2a1a10;border-color:#5a3c22}
  .tbl tr.hl td{background:#2a1a10}
  .rtab tr.me td{background:#12303f}
}
@media (max-width:700px){
  ul.cols{columns:1}
  .pad{grid-template-columns:1fr 1fr}
  /* the pool is ~150 px tall at phone width: the HUD would cover it and be clipped, so it flows
     under the canvas instead of over it */
  .hud{position:static;background:#0c2a3b;padding:6px;gap:6px}
  .hudbox{font-size:17px;min-width:0;flex:1 1 30%;padding:4px 7px}
  #hudMsg{top:12%}
  #hudMsg .big{font-size:32px}
}